docs: def write_data(self, offsets, data):
          # type: (Descriptor, Offsets, bytes) -> None
          """Write data to disk
          :param Descriptor self: this
          :param Offsets offsets: download offsets
          :param bytes data: data
          """
          if len(data) > 0:
              # offset from internal view
              pos = self.view.fd_start + offsets.fd_start
              with self.final_path.open('r+b') as fd:
                  fd.seek(pos, 0)
                  fd.write(data)